Author

Honors Program

Date of Award

5-2014

Thesis Professor(s)

Jonathan Peterson, Gary Wright

Thesis Professor Department

Health Sciences

Thesis Reader(s)

Michael McKamey, Burl Williams

Abstract

Non-alcoholic fatty liver disease (NAFLD) results from an unequal uptake/storage and export/oxidation of lipids within the liver and is often a secondary disease to type II diabetes (22). NAFLD causes this imbalance of lipids by altering glucose and lipid metabolism, which corresponds to a decrease in mitochondrial function leading to failure of the liver. One established treatment for type II diabetes and NAFLD is the drug metformin, which has similar properties to the newly discovered CTRP 3 protein which is part of a group of bioactive molecules secreted by adipose tissue, collectively termed adipokines (2-4). Both have similar effects on hepatic glucose and lipid metabolism and both specifically suppress hepatic gluconeogenesis (11, 17, 27, 29). The revolutionary Seahorse extracellular flux analyzer was used to measure the metabolism of H4IIE hepatocytes without use of radiolabeling (1). By detecting the Oxygen Consumption Rate (OCR) of hepatocytes the level of metabolic function within mitochondria can be measured. Once an effective protocol was established using this new technology, hepatocytes treated with metformin had a significantly lower OCR compared to control treated hepatocytes treated. However, H4IIE hepatocytes treated with metformin and palmitate had a significant increase in OCR and eventually equilibrated with the lower OCR of hepatocytes solely treated with metformin. With similar effect, hepatocytes treated with CTRP3 and palmitate caused a drastic increase in OCR while hepatocytes treated with only CTRP3 had a decrease in OCR. This suggests that CTRP3 increases fatty acid oxidation which decreases lipid concentrations within hepatocytes which could mean future protection of liver against NAFLD. In conclusion, our Seahorse XF analyzer models compare metformin and CTRP3’s similarities and suggest the possible liver protective functions of CTRP3. Our results will aid in future research of CTRP3 to further determine its possible uses as a treatment for liver-associated diseases.